San Antonio de Los Cobres, a community of 6,000 residents in the Andes Mountains in Argentina, faced a challenging arsenic concentration of up to 290 ppb in its water supply. It needed a solution to reduce the level to below the maximum contaminant level set by the World Health Organization (WHO) of 10 ppb.
Remote Andean town reduces arsenic with new treatment system
The U.S. Geological Survey (USGS) released a report in August revealing that 20% of untreated water samples from wells across the U.S. contain concentrations of trace elements exceeding human health benchmarks. Raissa Rocha, editorial intern for Water Quality Products, spoke with Joe Ayotte, USGS hydrologist and lead author of the study, about the report and the occurrence of trace elements in groundwater.
Raissa Rocha: What was the purpose of this study?
In 1986, California voters approved an initiative to address growing concerns about exposure to toxic chemicals. That initiative became the Safe Drinking Water and Toxic Enforcement Act of 1986, better known Proposition (Prop) 65. The act requires the state to publish a list of chemicals known to cause cancer, birth defects or other reproductive harm. This list, which must be updated at least once a year, has grown to include approximately 800 chemicals since it was first published in 1987.
Aiming for Arsenic
Preemptive testing can prevent costly penalties in California
Elevated levels of arsenic, iron and manganese prompted Brandywine Elementary School in Greenfield, Ind., a small town just east of Indianapolis, to seek a treatment solution for the school’s drinking water. The water system is served by one well that provides drinking water for approximately 330 students in kindergarten to fifth grade.
In July 2009, Ladd Eng. Inc. contacted AdEdge Technologies Inc. to provide a proposal for the Brandywine Elementary School in the Southern Hancock School District.
System remedies elementary school’s high arsenic, iron and manganese
Arsenic and its compounds have been known to be toxic for millennia. Arsenic trioxide (As2O3), often referred to as white arsenic, was a favored poison in the Middle Ages because it had little odor or taste, enabling it to be easily incorporated into the food or drink of a victim. As little as 300 mg can be fatal to an average person.
Solutions to an age-old threat
WQP spoke with Dow Water & Process Solutions Global Senior Application Development Specialist Fredrick W. Vance, Ph.D., about advances in arsenic removal research and the challenges of keeping costs at a minimum, responsible waste handling and continually improving adsorbent media.
LayneRT is an NSF/ANSI Standard 61 certified and approved arsenic removal media. It is a hydrous iron oxide-impregnated resin that efficiently binds arsenic and never needs backwashing. LayneRT was designed for use in the npXtra series of home treatment systems to effectively reduce arsenic. Tanks are connected by a proprietary control head that provides valves for sampling influent and effluent of both tanks.
Groundwater project demonstrates successful arsenic remediation